I am about to insulate a wall.
I am comparing Jablite (not basic polystyrene) to PIR board.
I can make the wall thicker when using Jablite rather than PIR so thickness is no problem.
It will not face compressive forces so no compressive strength issues.
The cost seems to be about half.
Both products seem to be combustible.
If I understand it right, PIR encapsulates a gas which leaks out over time eventually reducing the product to the same u-value as Polystyrene.
Why shouldn't I use Jablite?